Head suspension for disk drive

ABSTRACT

A head suspension for a disk drive includes a base ( 5 ) to be attached to a carriage, a load beam ( 3 ) having a rigid part ( 9 ) and a resilient part ( 11 ) supported by the base, to apply load on a data read/write head ( 19 ) arranged at a front end of the rigid part, a flexure ( 7 ) attached to the load beam and being provided with the head, and a guide face ( 27 ) formed on an edge ( 9   a ) of the rigid part where a jig is inserted, to guide the jig without wearing away the jig. The guide face is formed by providing the edge of the rigid part with an integral thin part that is tinner than the rigid part and bending the thin part, or by partly removing the edge of the rigid part. The jig is inserted into a head suspension module, which is made by arranging the head suspension and other identical head suspensions at regular intervals, such that teeth of the jig slide on the guide faces of the head suspensions to maintain spaces between the rigid parts of the head suspensions, to install the head suspension module into the disk drive such that the heads of the head suspensions face disks in the disk drive.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a head suspension for a diskdrive installed in an information processing apparatus such as apersonal computer.

[0003] 2. Description of the Related Art

[0004] A hard disk drive (HDD) records and reproduces infonnation to andfrom rotating magnetic or magneto-optical disks. The disks are supportedwith a carriage that is turned around a spindle by a positioning motor.

[0005] An example of the carriage is disclosed in U.S. Pat. No.4,167,765. The carriage of this disclosure includes a carriage arm, ahead suspension attached to a front end of the carriage arm a headattached to the head suspension, and a slider attached to the head. Theslider faces a disk. When the disk is rotated at high speed, the sliderslightly floats from the disk and an air bearing is formed between thedisk and the slider.

[0006]FIG. 1 is a sectional view partly showing a hard disk drive havinghead suspensions according to a related art. The disk drive 101 has acarriage 105 that is turned around a spindle 103 by a positioning motor107 such as a voice coil motor. The carriage 105 has a plurality of(four in FIG. 1) carriage arms 109, a head suspension 111 attached to afront end of each carriage arm 109, and a head 113 attached to a frontend of each head suspension 111.

[0007] The carriage 105 is turned around the spindle 103, to move theheads 113 onto a target track on disks 115. Each head 113 includes aslider 117 to be positioned onto a target track on the disk 115 and atransducer (not shown) supported with the slider 117.

[0008] When the disks 115 are rotated at high speed, air enters betweenthe disks 115 and the sliders 117 to slightly float the sliders 117 fromthe disks 115 and form air bearings between them.

[0009]FIGS. 2, 3A, and 3B show the head suspension 111. The headsuspension 111 includes a load beam 119 made of a precision thin platespring, a flexure 121 made of a very thin plate spring fixed to the loadbeam 119 by, for example, laser welding, and a base plate 123 fixed to abase of the load beam 119 by, for example, laser welding. The base plate123 is attached to a suspension attaching face of the carriage arm 109.

[0010] Recent hard disk drives employ high-density disks and drive thedisks at high speed. Such high-density disks involve narrow tracks, andtherefore, vibration such as butterfly mode vibration of the headsuspension 111 caused by air disturbance results in moving the head 113away from a track center.

[0011] It is important, therefore, to control the amplitudes andfrequencies of various resonance modes and air disturbance concerningthe head suspensions 111 and carriage arms 109 between the actuator 107and the sliders 117 in the disk drive 101. The recent high-density,high-speed disks require head suspensions of high rigidity and lowspring constant.

[0012] To achieve the requirements, the load beam 119 of FIGS. 3A and 3Bhas a channel 125. The load beam 119 has a rigid part 119 a that extendsfor a length L1 and needs high rigidity and a resilient part 119 b thatextends for a length L2 and needs a low spring constant. Tosimultaneously satisfy these needs, the resilient part 119 b is thinnedand edges of the rigid part 119 a are shaped into the channel 125 tocompensate the thinness of the rigid part 119 a that is restricted bythe thinness of the resilient part 119 b.

[0013] The channel 125 provides another function when the headsuspension 111 is installed into the disk drive 101.

[0014]FIG. 4 shows a comb 127 used when installing a head suspensionmodule into a disk drive. The head suspension module consists of aplurality of head suspensions arranged at regular intervals. In FIG. 4,the comb 127 has two teeth 129 and 131 corresponding to the number ofhead suspensions included in the module. FIG. 5 shows an example of thehead suspension module. This module consists of four head suspensions111.

[0015] The teeth 129 and 131 of the comb 127 are inserted into the headsuspension module as shown in FIG. 5 to maintain a given space betweenthe adjacent sliders 117 (FIG. 1). The comb 127 enables horizontally toinsert the head suspensions between the disks 115 (FIG. 1) so that thesliders 117 may face the disks 115. After the head suspension module isfixed at a proper position in the disk drive 101, the comb 127 isremoved from the head suspension module. In this way, the comb 127 isused to smoothly insert a module of head suspensions between disks in adisk drive.

[0016] When inserting the teeth 129 and 131 of the comb 127 between thehead suspensions 111, curves 125 a (FIG. 3B) of the channel 125 serve asguides to reduce friction between the load beams 119 and teeth 129 and131.

[0017] The channel 125, however, causes air disturbance when the disks115 are rotated at high speed, to flutter the load beams 119.

[0018] To solve the problem, this applicant has proposed a headsuspension for a disk drive in Japanese Patent Application No.11-263705. This head suspension simultaneously realizes high rigidityfor a rigid part (119 a) and a low spring constant for a resilient part(119 b) by separating the resilient part from the rigid part and bymaking the rigid part thicker than the resilient part. The rigid parthas no bends, and therefore, causes no air disturbance and load beamfluttering when disks are rotated at high speed.

[0019] Instead of having no bends, the rigid part of the disclosure hassharp edges 133 as shown in FIG. 6. When the tooth 129 of the comb 127is inserted between the head suspensions, the edge 133 of the rigid part119 a scrapes the teeth 129, and the scraped dust spreads over the disks115 to hinder the operation of the disk drive. In addition, the sharpedges 133 quickly wear the teeth of the comb 127, thereby deterioratingthe durability of the comb 127.

SUMMARY OF THE INVENTION

[0020] The present invention provides a head suspension for a diskdrive, capable of minimizing the wear of a comb even if the headsuspension has no rigidity-improving bends.

[0021] A first aspect of the present invention provides a headsuspension for a disk drive, having a base to be attached to a carriage,a load beam having a rigid part and a resilient part supported by thebase, to apply load on a data read/write head arranged at a front end ofthe rigid part, a flexure attached to the load beam and being providedwith the head, and a guide face formed on an edge of the rigid partwhere a jig is inserted, to guide the jig without wearing away the jig.The guide face is formed by providing the edge of the rigid part with anintegral thin part that is thinner than the rigid part and bending thethin part or by partly removing the edge of the rigid part. The jig isinserted into a head suspension module, which is made by arranging thehead suspension and other identical head suspensions at regularintervals, such that teeth of the jig slide on the guide faces of thehead suspensions to maintain spaces between then rigid parts of the headsuspensions, to install the head suspension module into the disk drivesuch that the heads of the head suspensions face disks in the diskdrive.

[0022] In the head suspension of the first aspect, a second aspect ofthe present invention forms the thin part by etching the edge of therigid part.

[0023] In the head suspension of any one of the first and secondaspects, a third aspect of the present invention makes an outer face ofa bend formed by bending the thin part protrude from a face of the rigidpart on which the flexure is arranged.

[0024] In the head suspension of the first aspect, a fourth aspect ofthe present invention partly removes the edge of the rigid part bypressing.

[0025] In the head suspension of the first aspect, a fifth aspect of thepresent invention provides the rigid part with at least three layersincluding metal plates and a resin layer sandwiched between the metalplates and forms the thin part from one of the metal plates.

[0026] In the head suspension of any one of the first, second, and fifthaspects, a sixth aspect of the present invention makes the height afterbent of the thin part smaller thin the thickness of the rigid part.

[0027] According to the first aspect a plurality of head suspensions arearranged at regular intervals to form a head suspension module. Themodule is installed into a disk drive by inserting a jig between therigid parts of the head suspensions such that teeth of the jig slide onthe guide faces of the head suspensions to maintain spaces between therigid parts. The jig enables easily to install the module into the diskdrive such that the heads at the front ends of the head suspensions facedisks in the disk drive.

[0028] The first aspect forms the guide face on the edge of the rigidpart where the jig is inserted. When the jig is inserted between therigid parts of the head suspension module, the jig is guided along theguide faces, to minimize the wearing of the jig, prevent the jig fromproducing abrasion dust and keep the disks clean.

[0029] Minimizing the wearing of the jig results in improving thedurability of the jig. The guide face is formed by providing the edge ofthe rigid part with an integral thin part that is thinner than the rigidpart and bending the thin part or by partly removing the edge of therigid part. The guide face is easy to form.

[0030] In addition to the effects of the first aspect, the second aspecteasily and precisely forms the thin part of the rigid partly etching theedge of the rigid part. The thin part is easy to bend to form the guideface. This results in extending the service life of an apparatus used toform the guide face.

[0031] In addition to the effects of the first and second aspects, thethird aspect makes an outer face of a bend formed by bending the thinpart protrude from a face of the rigid part on which the flexure isarranged. When the jig is inserted, the jig moves along the outer faceof the bend, to keep a space between the jig and the surface of therigid part, thereby protecting conductors formed on the flexure.

[0032] In addition to the effects of the first aspect, the fourth aspectpartly removes the edge of the rigid part by pressing, thereby easilyand correctly forming the guide face. The fourth aspect forms noprotrusion on the edges of the rigid part, to cause no air disturbancewhen the disks are rotated at high speed in the disk drive. Namely, thefourth aspect surely prevents vibration of the head suspension.

[0033] In addition to the effects of the first aspect, the fifth aspectprovides the rigid part of the head suspension with at least threelayers including metal plates and a resin layer sandwiched between themetal plates. The thin part of the rigid part is made from one of themetal plates, to easily form the guide face. The three-layered structureof the rigid part is effective to reduce the weight of the headsuspension and improve the rigidity thereof.

[0034] In addition to the effects of the first, second, and fifthaspects, the sixth aspect makes the height after bent of the thin partof the rigid part smaller than the thickness of the rigid part. As aresult, the thin part after bent causes no air disturbance when thedisks are rotated at high speed in the disk drive, thereby preventingvibration of the head suspension.

BRIEF DESCRIPTION OF THE DRAWINGS

[0035]FIG. 1 is a sectional view partly showing head suspensionsinstalled in a hard disk drive according to a related art;

[0036]FIG. 2 is a plan view showing one of the head suspensions of FIG.1 seen from a flexure side;

[0037]FIG. 3A is a perspective view showing a load beam of the headsuspension of FIG. 2;

[0038]FIG. 3B is a sectional view taken along a line SA-SA of FIG. 3A;

[0039]FIG. 4 is a perspective view partly showing a comb serving as ajig to install a head suspension module into a disk drive;

[0040]FIG. 5 is a perspective view showing the comb of FIG. 4 insertedinto a head suspension module;

[0041]FIG. 6 is a sectional view showing a tooth of the comb of FIG. 4in contact with a rigid part of a head suspension;

[0042]FIG. 7 is a plan view showing a head suspension seen from aflexure side according to a first embodiment of the present invention;

[0043]FIG. 8 is an enlarged perspective view showing a guide face of thehead suspension of FIG. 7 seen from the flexure side;

[0044]FIG. 9 is an enlarged perspective view showing the guide face seenfrom the opposite side of FIG. 8;

[0045]FIG. 10 is an enlarged sectional view showing the guide face ofFIG. 7;

[0046]FIG. 11A shows a thin part formed on the rigid part of the headsuspension according to the first embodiment;

[0047]FIG. 11B shows a guide face formed from the thin part of FIG. 11A;

[0048]FIG. 12 is a sectional view showing a rigid part of a headsuspension for a disk drive according to a second embodiment of thepresent invention;

[0049]FIG. 13A is a sectional view showing an edge of the rigid part ofthe second embodiment;

[0050]FIG. 13B is a sectional view showing a guide face formed on theedge of FIG. 13A;

[0051]FIG. 14A is a sectional view showing a thin part formed on a rigidpart of a head suspension for a disk drive according to a thirdembodiment of the present invention;

[0052]FIG. 14B is a sectional view showing a guide face formed from thethin part of FIG. 14A;

[0053]FIG. 15 is a perspective view showing a head suspension for a diskdrive according to a fourth embodiment of the present invention;

[0054]FIG. 16 is a perspective view showing a head suspension for a diskdrive according to a fifth embodiment of the present invention;

[0055]FIG. 17 is a perspective view showing a load beam of a headsuspension for a disk drive according to a sixth embodiment of thepresent invention;

[0056]FIG. 18 is a sectional view taken along a line SB-SB of FIG. 17;

[0057]FIG. 19 is a perspective view showing a load beam of a headsuspension for a disk drive according to a modification of the sixthembodiment; and

[0058]FIG. 20 is a perspective view showing a load beam of a headsuspension for a disk drive according to a seventh embodiment of thepresent invention.

DETAILED DESCRIPTION OF EMBODIMENTS First Embodiment

[0059]FIG. 7 is a plan view showing a head suspension 1 for a disk driveaccording to the first embodiment of the present invention. The headsuspension 1 includes a load beam 3, a base 5, and a flexure 7.

[0060] The load beam 3 has a rigid part 9 and a resilient part 11. Therigid part 9 is made of, for example, stainless steel and is relativelythick, for example, 0.1 mm thick.

[0061] The resilient part 11 is independent of the rigid part 9 and ismade of, for example, a thin stainless steel rolled plate. The resilientpart 11 has a precision low spring constant that is lower than that ofthe rigid part 9. The thickness of the resilient part 11 is, forexample, t=0.040 mm. An end of the resilient part 11 is fixed to a rearend 9 c of the rigid part 9 by, for example, laser welding. The otherend of the resilient part 11 forms an integral reinforcing plate 13.

[0062] The base 5 has a base plate 15, which is laid over thereinforcing plate 13 and fixed thereto by, for example, laser welding.Namely, the base plate 15 is reinforced with the reinforcing plate 13,to form the base 5.

[0063] The flexure 7 includes a metal base made of, for example, aresilient thin stainless rolled plate. An insulating layer is formed onthe metal base, and conductors 17 are formed on the insulating layer.The flexure 7 is fixed to the rigid part 9 by, for example, laserwelding. One ends of the conductors 17 are electrically connected toterminals 21 of a head 19, and the other ends thereof are electricallyconnected to terminals 23 of the base 5. The head 19 has a slider 25.

[0064] The rigid part 9 has longitudinal edges 9 a. Each of the edges 9a is provided with a guide face 27 at a position where a tooth of a comb(such as the tooth 129 of the comb 127 of FIG. 4) is inserted. Accordingto the first embodiment, the guide face 27 is formed in a range S alongthe edge 9 a in front of the resilient part 11. The guide face 27 of thefirst embodiment is formed on each edge 9 a to maintain the horizontalbalance of the rigid part 9. The guide face 27 may be formed on one edge9 a where the comb is inserted.

[0065]FIGS. 8 and 9 are enlarged perspective views showing the guideface 27, in which FIG. 8 is a view seen from the flexure 7 side and FIG.9 is a view seen from the opposite side. The guide face 27 is formed onthe edge 9 a of the rigid part 9.

[0066]FIG. 10 is a sectional view showing the guide face 27. Accordingto the first embodiment, each edge 9 a of the rigid part 9 is providedwith a thin part 29 thinner than the rigid part 9, and the thin part 29is bent to form the guide face 27. The guide face 27 has a slant 27 aand a curve 27 b. The curve 27 b smoothly connects the slant 27 a to asurface 9 b of the rigid part 9.

[0067] An inclination angle of the slant 27 a relative to the surface 9b is, for example, θ=40°. An extension of the slant 27 a and anextension of the surface 9 b form an intersection 31. The intersection31 is distanced from a front end 33 of the thin part 29 by, for example,H=0.05 mm. The inclination θ and distance H are optional. The height ofthe bend from the surface 9 b is lower than the height of the rigid part9. The height of the bend from the surface 9 b may be greater than theheight of the rigid part 9.

[0068]FIGS. 11A and 11B show a method of forming the guide face 27. InFIG. 11A, the edge 9 a of the rigid part 9 is etched to form a recess 35and the thin part 29 thinner than the rigid part 9. In FIG. 11B, a pressis used to smoothly bend the thin part 29 to form the guide face 27along the edge 9 a. In this way, the guide face 27 is easily andcorrectly formed by etching and pressing. The pressing needs only smallforce, to maintain proper operation of the press for a long time.

[0069] A plurality of head suspensions 1 each having the guide faces 27are assembled into a head suspension module, and the module is installedinto a disk drive by inserting the comb 127 into the rigid parts 9 asshown in FIG. 5. At this time, the teeth of the comb 127 contact withthe slants 27 a, enter between the rigid parts 9, gradually widen spacesbetween the rigid parts 9, slide on the slants 27 a and curves 27 b, andmove over the surfaces 9 b of the rigid parts 9. As a result the teethof the comb 127 are not rubbed by the edges of the rigid parts 9, tothereby are not or slightly worn by the edges of the rigid parts 9.

[0070] The head suspension module is installed as shown in FIG. 1 sothat the sliders 25 of the heads 19 face the disks 115. In this case,the comb 127 produces substantially no abrasion dust due to the guidefaces 27, to keep the disks 115 clean and improve the durability of thecomb 127.

[0071] According to the first embodiment, the rigid part 9 is thick andhighly rigid, and the edges 9 a of the rigid part 9 are provided withthe thin parts 29 to easily form the guide faces 27.

[0072] According to the first embodiment, the rigid part 9 maintainshigh rigidity, and at the same time, the separate resilient part 11realizes a low spring constant. In the load beam 3, the material andthickness of the rigid part 9 are not restricted by those of theresilient part 11. Namely, the rigid part 9 and resilient part 11 mayhave individual materials and thicknesses, to satisfy requirements forthe head suspension 1.

[0073] The rigid part 9 realizes high rigidity without a channel shape,and the height after bent of the thin part 29 is lower than the heightof the rigid part 9. As a result, the rigid part 9 shows low airresistance. This minimizes air disturbance when the disks 115 arerotated at high speed and prevents the fluttering of the head suspension1.

Second Embodiment

[0074]FIGS. 12, 13A, and 13B show a rigid part 9 of a head suspensionfor a disk drive according to the second embodiment of the presentinvention. The second embodiment partly removes each edge 9 a of therigid part 9 and forms a guide face 27A. The guide face 27A has aninclination angle of for example, θ1=40° relative to a surface 9 b ofthe rigid part 9. The width of the guide face 27A is, for example,H1=0.05 nm. The inclination angle θ1 and width H1 are optional.

[0075]FIGS. 13A and 13B show a method of forming the guide face 27A. InFIG. 13A, a press is used to remove an edge comer 37 of the rigid part9, thereby forming the guide face 27A as shown in FIG. 13B.

[0076] The guide face 27A of the second embodiment provides the sameeffects as the guide face 27 of the first embodiment. The secondembodiment forms the guide face 27A by removing the edge comer 37without bending. Accordingly, the guide face 27A is easier to form thanthe guide face 27 of the first embodiment. The guide face 27A has nobend, and therefore, is free from air disturbance and surely preventsvibration of the head suspension. The guide face 27A formed by pressingis advantageous in maintaining the weight balance of the head suspensioneven if the guide face 27A is formed on one edge of the rigid part 9.

[0077] Removing the edge comer 37 may be carried out by etching. Theguide face 27A may have a curve smoothly connected to the surface 9 b ofthe rigid part 9.

Third Embodiment

[0078]FIGS. 14A and 14B show a rigid part 9 of a head suspension for adisk drive according to the third embodiment of the present invention InFIG. 14A, each edge 9 a of the rigid part 9 is etched to form a recess35B and a thin part 29B thinner than the rigid part 9.

[0079] In FIG. 14B, a press is used to bend the thin part 29B, to form aguide face 27B having a slant 27Ba and a curve 27Bb. The height afterbent of the thin part 29B is set like that of the thin part 29 of thefirst embodiment. The curve 27Bb is an outer face of a bend 29Ba of thethin part 29B and protrudes from the surface 9 b of the rigid part 9.According to the third embodiment, the height of the protrusion of thecurve 27Bb from the surface 9 b is equal to or greater than the heightof a flexure 7 arranged on the surface 9 b. The height of the protrusionof the curve 27Bb from the surface 9 b, however, is optional.

[0080] The third embodiment provides substantially the same effects asthe first embodiment According to the third embodiment, the curve 27Bbprotrudes from the surface 9 b. A tooth of a comb (for example, thetooth 129 of the comb 127 of FIG. 4) moves on the curve 27Bb and keeps aspace from the surface 9 b, thereby protecting conductors formed on theflexure 7. If the height of the protrusion of the curve 27Bb from thesurface 9 b is equal to or greater than the height of the flexure 7, theconductors on the flexure 7 are surely protected.

Fourth Embodiment

[0081]FIG. 15 is a perspective view showing a head suspension 1C for adisk drive according to the fourth embodiment of the present invention.In FIG. 15, parts corresponding to those of the first embodiment arerepresented with like reference numerals.

[0082] The head suspension 1C has a load beam 3C and a base 5C. The loadbeam 3C includes a rigid part 9C and a resilient part 11C having arectangular frame shape. The base 5C consists of only a base plate 15C.An end 11Ca of the resilient part 11C is laid on an end 9Ca of the rigidpart 9C and is fixed thereto by, for example, laser welding. Another end11Cb of the resilient part 11C is laid on a front end of the base plate15C and is fixed thereto by, for example, laser welding. The resilientpart 11C has an opening 11Cc and sides 11Cd and 11Ce to provide a lowspring constant.

[0083] The rigid part 9C has guide faces 27 where a tooth of a comb(such as the tooth 129 of the comb 127 of FIG. 4) is inserted The fourthembodiment forms the guide face 27 on each edge of the rigid part 9C tomaintain the horizontal weight balance of the head suspension 1C. Theguide face 27 may be formed only on one edge of the rigid part 9C wherea tooth of the comb is inserted. The guide face 27 may be any one of theguide faces of the second to third embodiments.

[0084] The fourth embodiment provides the same effects as the first tothird embodiments.

Fifth Embodiment

[0085]FIG. 16 is a perspective view showing a head suspension 1D for adisk drive according to the fifth embodiment of the present invention.In FIG. 16, parts corresponding to those of FIG. 15 are represented withlike reference numerals.

[0086] The head suspension 1D has a base plate 15D that is longer thanthe base plate 15C of FIG. 15. The base plate 15D also serves as acarriage arm (109 of FIG. 1).

[0087] A guide face 27 is formed on each edge of a rigid part 9C of thehead suspension 1D, to provide the same effects as the fourthembodiment. The guide face 27 may be any one of the guide faces of thefirst to third embodiments.

Sixth Embodiment

[0088]FIG. 17 is a perspective view showing a load beam 3E of a headsuspension for a disk drive according to the sixth embodiment of thepresent invention, and FIG. 18 is a sectional view taken along a lineSB-SB of FIG. 17.

[0089] In FIG. 17, only the load beam 3E proper is shown and other partsincluding a flexure are omitted. The load beam 3E has a rigid part 9Eand a resilient part 11E. The rigid part 9E has substantially a triangleshape with a base end 9Eb gradually narrowing toward a front end 9Ea.The thickness of the rigid part 9E is, for example, t=100 μm.

[0090] Referring to FIGS. 17 and 18, the rigid part 9E has a three-layerstructure with metal plates 37 a and 37 b sandwiching a resin layer 37 cand bonded each other. The metal plates 37 a and 37 b are made of, forexample, stainless steel (SUS). The thickness of the metal plate 37 ais, for example, t=38 μm, and the thickness of the metal plate 37 b is,for example, t=20 μm.

[0091] The resin layer 37 c is a resin plate made of, for example,polyimide (PI) resin or epoxy resin. The thickness of the resin layer 37c is, for example, t=42 μm. The total thickness of the metal plates 37 aand 37 b and resin layer 37 c is set to be 100 μm. These thicknesses areonly examples. Depending on rigidity set for the rigid part 9E, theindividual thicknesses of the metal plates 37 a and 37 b and resin layer37 c and the total thickness thereof are properly set.

[0092] The rigid part 9E has bends 39, which are integral with the metalplate 37 b. Each bend 39 is lower than the rigid part 9E. The bends 39are formed by preparing three layers (37 a,37 b, 37 c) havingprotrusions corresponding to the bends 39, etching off the protrusionson the metal plate 37 a and resin layer 37 c to leave the protrusions onthe metal plate 37 b, and bending the protrusions on the metal plate 37b by press.

[0093] The bends 39 provide guide faces 27E. According to the sixthembodiment, the guide faces 27E are formed on both edges of the rigidpart 9E to maintain the horizontal weight balance of the load beam 3E.The guide face 27E may be formed only on one edge of the rigid part 9Ewhere a tooth of a comb (such as the tooth 129 of the comb 127 of FIG.4) is inserted.

[0094] According to the sixth embodiment the height of the bend 39 isequal to a surface 9Eb of the rigid part 9E. The height of the bend 39may be lower than the surface 9Eb, i.e., smaller than the thickness ofthe rigid part 9E. The height of the bend 39 maybe greater than thethickness of the rigid part 9E.

[0095] The front end 9Ea of the rigid part 9E consists of only the metalplate 37 b and has a dimple 41. The front end 9Ea is formed by, forexample, etching, off the metal plate 37 a and resin layer 37 c.

[0096] The resilient part 11E is integral with the metal plate 37 a atan end of the rigid part 9E. Namely, the resilient part 11E has asingle-layer structure. The resilient part 11E is made of, for example,stainless steel. The thickness of the resilient part 11E is, forexample, t=38 μm. The resilient part 11E has an opening 11Ea and sides11Ec and 11Ed to provide a low spring constant.

[0097] Opposite to the rigid part 9E, the resilient part 11E is integralwith a reinforcing metal plate 43 a for reinforcing a base. The metalplate 43 a is made of, for example, stainless steel, and the thicknessthereof is, for example, t=38 μm. The metal plate 43 a and anotherreinforcing metal plate 43 b sandwich a resin layer 43 c and are bondedeach other to form a three-layer reinforcing part 45.

[0098] The metal plates 43 a and 43 b and resin layer 43 c of thereinforcing part 45 resemble the metal plates 37 a and 37 b and resinlayer 37 c of the rigid part 9E. The metal plate 43 b is made ofstainless steel, and the thickness thereof is, for example, t=20 μm. Theresin layer 43 c is made of polyimide resin or epoxy resin, and thethickness thereof is, for example, t=42 μm.

[0099] The reinforcing part 45 is attached to a base plate and fixedthereto by, for example, laser welding. The base plate is attached to acarriage arm.

[0100] The guide faces 27E of the sixth embodiment provide the sameeffects as the first to fifth embodiments. The height of each bend 39 issubstantially equal to the height of the surface 9Eb of the rigid part9E, and therefore, causes no air disturbance and prevents vibration ofthe load beam 3E.

[0101] According to the sixth embodiment, the bends 39 are formed onlyon the metal plate 37 b, and therefore, are easy to form with the dimple41.

[0102] The rigid part 9E has the three-layer structure interposing theresin layer 37 c, to remarkably improve the rigidity of the rigid part9E. The interposed resin layer 37 c provides a damper effect Theresilient part 11E is made of a single plate to easily provide a lowspring constant. As a result, the head suspension of the sixthembodiment realizes a high resonance frequency and the damper effect, tosurely prevent the fluttering of the head suspension.

[0103] The three-layer reinforcing part 45 interposing the resin layer43 c provides high rigidity to surely attach the base to a carriage arm.The load beam 3E as a whole is a three-layer structure with theinterposed resin layers 37 c and 43 c, to greatly reduce the weight ofthe head suspension.

[0104] Each bend 39 may be inclined so that the guide face 27E may havea slant and a curve. The resilient part 11E may be integral with themetal plate 37 b as shown in FIG. 19. In this case, the thickness of themetal plate 37 b is equalized with the thickness of the resilient part11E.

[0105] According to the sixth embodiment, the resilient part 11E mayhave a two-layer structure consisting of a metal plate and a resinlayer, or a three-layer structure consisting of two metal platessandwiching a resin layer. In this case, the rigid part 9E or the rigidpart 9E and reinforcing part 45 may have a multilayer structure made ofmetal and resin layers whose number is greater than the number of layersof the resilient part 11E.

Seventh Embodiment

[0106]FIG. 20 is a perspective view showing a load beam 3F of a headsuspension for a disk drive according to the seventh embodiment of thepresent invention. In FIG. 20, parts corresponding to those of the sixthembodiment are represented with like reference numerals.

[0107] In the load beam 3F, a rigid part 9E and a reinforcing part 45have each a three-layer structure like the sixth embodiment. Inaddition, are resilient part 11F also has a three-layer structureconsisting of metal plates 47 a and 47 b sandwiching a resin layer 47 c.The metal plate 47 a is integral with a metal plate 37 a and areinforcing metal plate 43 a, and these metal plates have the samethickness. The metal plate 47 b is integral with a metal plate 37 b anda reinforcing metal plate 43 b, and these metal plates have the samethickness. The resin layer 47 c is integral with resin layers 37 c and43 c, and these resin layers have the same thickness.

[0108] The seventh embodiment provides the same effects as the sixthembodiment.

What is claimed is:
 1. A head suspension for a disk drive, comprising: abase to be attached to a carriage; a load beam having a rigid part and aresilient part supported by the base, to apply load on a data read/writehead arranged at a front end of the rigid part; a flexure attached tothe load beam and being provided with the head; and a guide face formedon an edge of the rigid part where a jig is inserted, to guide the jigwithout wearing away the jig, the guide face being formed by providingthe edge of the rigid part with an integral thin part that is thinnerthan the rigid part and bending the thin part, or by partly removing theedge of the rigid part; the jig being inserted into a head suspensionmodule, which is made by arranging the head suspension and otheridentical head suspensions at regular intervals, such that teeth of thejig slide on the guide faces of the head suspensions to maintain spacesbetween the rigid parts of the head suspensions, to install the headsuspension module into the disk drive such that the heads of the headsuspensions face disks in the disk drive.
 2. The head suspension for adisk drive of claim 1, wherein: the thin part provided for the rigidpart is formed by etching the edge of the rigid part.
 3. The headsuspension for a disk drive of claims 1, wherein: an outer face of abend formed by bending the thin part of the rigid part protrudes from aface of the rigid part on which the flexure is arranged.
 4. The headsuspension for a disk drive of claims 2, wherein: an outer face of abend formed by bending the thin part of the rigid part protrudes from aface of the rigid part on which the flexure is arranged.
 5. The headsuspension for a disk drive of claim 1, wherein: the edge of the rigidpart is partly removed by pressing.
 6. The head suspension for a diskdrive of claim 1, wherein: the rigid part consists of at least threelayers including metal plates and a resin layer sandwiched between themetal plates; and the thin part of the rigid part is made from one ofthe metal plates.
 7. The head suspension for a disk drive claims 1,wherein: the height after bent of the thin part of the rigid part issmaller than the thickness of the rigid part.
 8. The head suspension fora disk chive of claims 2, wherein: the height after bent of the thinpart of the rigid part is smaller than the thickness of the rigid part.9. The head suspension for a disk drive of claims 6, wherein: the heightafter bent of the thin part of the rigid part is smaller than thethickness of the rigid part.